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Game 26, Mariners at Yankees

After yesterday’s rain-out (and you know you’re a baseball blogger when you kind of look forward to talking about David Phelps), the Yankees reshuffled their rotation, so the M’s face righty Hiroki Kuroda. Before Tanaka, before Iwakuma, before Uehara turned unhittable, there was Hiroki Kuroda. He’s by no means the first pitcher to feature a splitter, and he’s not even the first Japanese pitcher to find success in MLB in part thanks to his split-finger. But Kuroda’s success and, importantly, his evolution in the majors probably contributed to the bidding war around Tanaka.

To review, Kuroda signed with the Dodgers before the 2008 season, and spent four solid, almost insanely consistent seasons in LA. He moved to New York in 2012 and continued to post FIPs in the mid-3s despite the small park. Kuroda’s been one of the best free agent acquisitions in a long time for an organization known mostly for free agent acquisitions. His splitter’s helped him against lefties, and it’s helped avoid serious home run issued in hitter-friendly new Yankee stadium. What’s interesting, though, is that he wasn’t always a fastball/splitter pitcher. Only in his last season in LA did Kuroda throw appreciably more splitters than sliders…to left-handed hitters. To righties, he’s still a fastball/slider guy.

It’s worth noting that the splitters that Kuroda/Iwakuma/Tanaka/Alex Cobb throw are quite a bit different from the pitch that Dan Haren and Ubaldo Jimenez call a splitter. You can read Dan Haren describe his pitch to Eno Sarris here, but from a movement perspective, it’s more similar to a change-up, with arm-side run compared to the four-seam and moderate sink. It’s also slower – it’s around 8-10mph slower than the FB. Kuroda/Iwakuma/Tanaka/Cobb throw a pitch that’s maybe 4-6mph slower than a four-seam (Kuroda’s is 87, Iwakuma’s is 86), with no more arm-side run than the four-seam and a more pronounced downward dive. That means they can use it in different ways – whereas Dan Haren talks about being able to use it within the strike zone, and get *called* strikes with it, Kuroda/Iwakuma essentially avoid the strikezone completely, but rack up swinging strikes anyway.

So does Kuroda have Iwakuma’s reverse splits? No, he doesn’t – they’re completely normal. I do wonder, though, what they’d look like if he wasn’t so enamored with his slider, especially early on. In his career, lefties have hit five times as many HRs on Kuroda’s slider as his split, despite the fact that he’s thrown them about the same number of each. Technically, Iwakuma’s given up more HRs to lefties with HIS slider too, despite the fact that he rarely throws it to them.

Still, Kuroda’s nearing in on 40, and he’s not been as sharp this year. He’s been worse against lefties, but significantly worse against righties, though it’s obviously too soon to know if that means anything. The M’s have something of a re-jiggered line-up as they try to take this series and keep themselves on the periphery of the chase.

Note: This is a seattlepi.com reader blog. It is not written or edited by the P-I. The authors are solely responsible for content. E-mail us at newmedia@seattlepi.com if you consider a post inappropriate..